Bubba Watson secured his second PGA Tour title of 2011 after beating fellow American Webb Simpson in a play-off at the Zurich Classic of New Orleans.
Simpson had led by three shots with seven to play but suffered an unfortunate penalty stroke at 15 when his ball moved as he went to tap in for par.
As he'd grounded his club the infringement cost him a shot and meant the scores were tied at 15-under after Simpson had earlier bogeyed 12 and Watson had cut the gap to a shot with a birdie at 13.
Both made pars at 16 and 17 before Watson had a nine foot birdie putt at the last to take victory.
It missed, meaning both signed for 69s to finish two shots clear of the field at 15-under after they'd started the final round as joint leaders.
Simpson appeared to have the edge at the first extra hole, the par five 18th, but Watson stroked in a 10 foot birdie putt to match Simpson's four and the play-off continued.
Playing the 18th again, Watson flirted with the water down the right with his tee-shot, his ball eventually catching a bunker.
But from there he lashed a second shot onto the green and his two-putt birdie was enough to secure victory after Simpson, seeking his first PGA Tour win, failed to get up and down from sand.
"Somehow now I've got three," he said after ending a breezy afternoon at the TPC Louisiana with his third title in 11 months.
"A year ago I was a good player who (had) never won, and now I've got three under my belt so it's crazy. It's something that I could never dream of.
"For me to get one was unbelievable. My career was complete. I've done it. Then for me to get another one just adds to my career. It's something I've dreamed about doing."
Jason Dufner, with a best of the day 66, tied for third place with fellow American Tommy Gainey and Korean KJ Choi - the trio all finishing two shots back on 13-under.
England's Luke Donald finished strongly with four birdies in his final six holes to take a share of eighth.
It always looked like developing into a duel between Watson and Simpson after the two made blistering starts.
Simpson birdied the first, both traded eagles at the second and Watson birdied the third and fourth to take the lead at 16-under.
Another Simpson birdie at five levelled it up again but at the ninth Watson fell two behind after hitting his tee-shot into water at the short par three and racking up a double bogey.
Simpson extended the lead to three shots with a superb second to the 10th to go three clear but a combination of some narrowly birdie putts and that unfortunate penalty stroke allowed Watson to reel him in.
With the victory Watson moves up to number 10 in the world golf rankings.
But for Simpson the search for a maiden title continues as he reflected on what might have been.
"A little unfortunate what happened on 15," he said. "I had better limit my comments on that rule, because I think it's such a bad rule.
"I hit some good shots coming in and gave myself a chance. Unfortunately, I just came up a little bit short.
"It was fun being out there with Bubba. He's a great friend and a great champion. I'm happy for him. He hit some great shots and great putts coming in."